Biology Reference
In-Depth Information
pachysandra, pepper, pieris, pine, rhubarb, soy-
bean, strawberry, wheat, and yew.
Helicotylenchus multicinctus
Cobb's Spiral
Nematode
. Associated with roots of many
plants, including azalea, cherry, cranberry,
marsh grass, hibiscus, peach, pine, spruce, and
yew.
Helicotylenchus nannus
Steiner's Spiral Nem-
atode
, a small species common in the Southeast.
Found damaging roots of apple, azalea, boxwood,
asparagus fern, calathea, camellia, centipede
grass, civet bean, gardenia, peperomia, philoden-
dron, rubber-plant, royal palm, laurel oak, soy-
bean, peanut, and tomato. There is a gradual
decline, stunting, and failure to form flower buds.
Helicotylenchus
Dolichodorus
Dolichodoriadae. Awl nematodes similar to sting
nematodes with long stylet with well-developed
knobs; coarsely annulated cuticle; both sexes
wormlike; male tail has a bursa (lateral exten-
sion); female has two ovaries; ectoparasites.
Dolichodorus heterocephalus
Awl Nematode
,
causing decline of celery, bean, tomato, corn,
pepper, and water chestnut in the Southeast, also
recorded on pecan. It feeds largely on root tips
and sometimes along the side of roots, causing
necrotic lesions. It also feeds on germinating
seeds and hypocotyls, sometimes penetrating
the seedcoat to reach the embryo. Poor seedling
emergence may be due to this nematode.
Dolichodorus (Neodolichlodorus) obtusus On
arctostaphylus and pecan, California.
pseudorobustus On
corn,
grape, tomato, and soybean.
Hemicriconemoides
Dorylaimus
Criconematidae. Ectoparasites; female with
cuticular sheath, anchor-shaped stylet with ante-
riorly concave knobs; males without sheath or
stylet. Commonly associated with turf and
woody plants in warm climates, but pathogenic-
ity not yet demonstrated.
Hemicriconemoides biformis
Oak Sheathoid
Nematode
. On roots of oak, Florida.
Hemicriconemoides chitwoodi Associated
with stunting of camellias.
Hemicriconemoides floridensis
Pine
Sheathoid Nematode
. On pine.
Hemicriconemoides gaddi On camellias.
Hemicriconemoides
Dorylaimidae. Spear nematodes, with an
odontostylet (hollow tooth), bottle-shaped esoph-
agus; cuticle with longitudinal ridges; both sexes
wormlike, tails rounded to cone-shaped; not
proven plant parasites.
Dorylaimus spp. Found in soil near soybean,
sweet potato, and other plants but not known as
a pathogen.
Helicotylenchus
wessoni On
myrica,
Hoplolaimidae. Spiral nematodes, ectoparasites
or semiendoparasites; long strong stylet with
basal knobs; cuticle annulated. The head is
inserted in a root, but the body remains outside
in a ventrically curved spiral with one or more
turns.
Helicotylenchus dihystera On gardenia, corn,
and bluegrass.
Helicotylenchus erythrinae
Zimmerman's
Spiral Nematode
. Rather common in Florida
around roots of grasses. Present in other states
on blueberry, boxwood, cauliflower, cedar, clo-
vers, corn, cranberry,
Florida.
Hemicycliophora
Criconematidae. Sheath nematodes; ectopara-
sites with sedentary habits; female retains last
molt as an extra cuticle; knobs of stylet spheroid;
males rare, without stylet.
Hemicycliophora arenaria Causing root galls
on rough lemon, also reproducing in tomato, pep-
per, celery, squash, and bean. Celery has large,
multibranched galls.
turf grasses, oak, oat,
